1. Field of the Invention
The present invention relates to locking structure for an externally threaded fastener, e.g., a screw or bolt, to inhibit its becoming totally unthreaded by accident (for instance through vibration or insufficient tightening) from an object having an internally threaded through bore through which the externally threaded fastener extends.
2. Description of the Prior Art
Structures to prevent the total unintended unthreading of external threaded fasteners from threadably engaged internally threaded objects are well known in the prior art.
Such unthreading cannot only lose the fastener but also cause it catastrophically to fall into meshing gears, machinery or high-voltage electrics, etc. Prior art fastener lock structures and methods comprise sticky or viscous or setting substances in the threads, which have only a limited time of effectivity friction devices in the threading, and/or wire passed through a hole in the fastener. The use of lock wires is expensive and time consuming although reliable.